Test Two Nervous Tissue Flashcards
The central nervous system consists of
Brain and spinal cord
Why called central nervous system
In the central axis of the body
The central nervous system is the part of the nervous system that…
Controls our body
Peripheral nervous system is made up of
Plexus of the body and main nerves of the body
The peripheral nervous system originates from where
Brain and spinal cord
What is a plexus
Groups of nerves
How many cranial nerves
12
Cranial nerves originate where and innervate where
From brain and innervate the head and neck
How many pair of spinal nerves
33
The spinal nerves attach where and innervate what
Originate from the spinal cord and innervate the body
What are sensory nerves
Carry information towards the CNS
What are motor nerves
Carry information away from CNS
What are mixed nerves
Nerves that are motor and sensory
Autonomic system innervates what
To the involuntary muscles of the body
Specifically what muscles does the autonomic nervous system innervates
Smooth and cardiac muscle
What are the two subsections of the autonomic nervous system
Sympathetic and parasympathetic
The sympathetic is used for
Flight or flight, survival
The parasympathetic is used for
Rest and digest, returns the body back to resting state after sympathetic response
Function of glial cells
Support cells of the nervous system
How many glial cells per neuron
10 glial cells
What are the three things astrocytes do
Storage, scavengers and support
How are astrocytes storage cells
Store metabolites such as sugar and deliver them to neuron
How are astrocytes work as scavengers
Responsible for cleaning up the environment of the neuron
How do astrocytes work as support
Physical support for neurons, form scaffolding
What are microvilli
Used for protection against pathogens by attacking and destroying foreign molecules
What nerve cell is the macrophage of the CNS
Microglia
What are oligrodendrocytes
Secretion and maintenance of myelin
If you increase myelin, what happens to conduction velocity
Increase
What are ependymal cells
Make cerebral spinal fluid
What is cerebral spinal fluid
Modified blood plasma
A nerve cell is also known as
Neuron
What are neurons
Functional cells of the nervous system
What is the function of neurons
Conduct action potentials
Nervous system works on a rate of what
Action potentials
What is the binary code of the nervous system
Either the neuron fires or it doesn’t
What are the three parts of the neuron
Cell body, dendrites and axons
What is the largest part of the neuron
Cell body
Where do most of the cellular processes take place in the neuron
Cell body
What is found in the cell body of the neuron
Nucleus, Nissl bodies, protein synthesis organelles, mitochondria, lysosomes, ER and golgi
What are Nissl bodies made of
RER, ribosomes and polysomes
Function of dendrites
Carry action potential toward cell body
How many dendrites per neuron
0 to 16
What is the primary dendrite
Process that connects to the body
Dendrites begin to branch when
They move away from the body forming the dendritic tree
The purpose of branching the dendrites
Increase surface area for synaptic contact
What are inside dendrites
Will contain all the same organelles as the cell body but the nucleus
Function of axon
Process that carries action potential away from the cell body
How many axons per neuron
One
Purpose of myelin sheath
Increase conduction velocity
What are the nodes of ranvier
Point in myelin sheath that has break points
How does the action potential move down the axon
AP jumps from node to node
Purpose of myelin and nodes of ranvier
Myelin helps by not having the membrane depolarize throughout just at the nodes
What are telodendria
Area of axon beginning to flare out
Purpose of telondendria
Increases surface are and allows for multiple terminal boutons
What are terminal boutons
End of the axon terminals where synapses occur
More terminal boutons mean what
More efficient the nervous system
You can classify neurons based on what
Number of processes
What neuron does not exist in human nervous system
Unipolar
What are unipolar neurons
Has one axon and no dendrites at the body, simplest neuron
Where does synapse occur at the unipolar neuron
At the body
What are pseudounipolar neuron
Two processes attach to the cell body but it looks like one under light microscope
Where do you see pseudounipolar in the body
General sensory systems such as pain, temp or touch
What are bipolar neurons
Cell body with axon and dendrites but the processes are on opposite sides of the body
Where are bipolar neurons found
In special senses such as retina of eye, auditory system or vestibular system
What are multipolar neurons
Cell body and axon with more than one dendrite
Where do you find multipolar neurons
Motor systems such as ventral horn of spinal cord
What is the most numerous neurons in the human
Multipolar neuron due to the complexity of the nervous system
